[PATCH 2/3] mm/vmalloc: extract vmap_insert_free_area helper

[Ye Liu]

From: Ye Liu <liuye@xxxxxxxxxx>

The allocation and insertion of a free vmap_area is duplicated
between the loop body and the tail of vmap_init_free_space.  Factor
it into a small helper so the main function only deals with computing
the free gaps between busy regions.

Signed-off-by: Ye Liu <liuye@xxxxxxxxxx>
---
 mm/vmalloc.c | 41 ++++++++++++++++++-----------------------
 1 file changed, 18 insertions(+), 23 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 117483dd048c..797933ba9451 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -5433,11 +5433,23 @@ module_init(proc_vmalloc_init);
 
 #endif
 
+static void __init vmap_insert_free_area(unsigned long start, unsigned long end)
+{
+	struct vmap_area *free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
+
+	if (!WARN_ON_ONCE(!free)) {
+		free->va_start = start;
+		free->va_end = end;
+		insert_vmap_area_augment(free, NULL,
+					 &free_vmap_area_root,
+					 &free_vmap_area_list);
+	}
+}
+
 static void __init vmap_init_free_space(void)
 {
 	unsigned long vmap_start = 1;
 	const unsigned long vmap_end = ULONG_MAX;
-	struct vmap_area *free;
 	struct vm_struct *busy;
 
 	/*
@@ -5447,32 +5459,15 @@ static void __init vmap_init_free_space(void)
 	 *  |<--------------------------------->|
 	 */
 	for (busy = vmlist; busy; busy = busy->next) {
-		if ((unsigned long) busy->addr - vmap_start > 0) {
-			free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
-			if (!WARN_ON_ONCE(!free)) {
-				free->va_start = vmap_start;
-				free->va_end = (unsigned long) busy->addr;
-
-				insert_vmap_area_augment(free, NULL,
-					&free_vmap_area_root,
-						&free_vmap_area_list);
-			}
-		}
+		if ((unsigned long)busy->addr - vmap_start > 0)
+			vmap_insert_free_area(vmap_start,
+					      (unsigned long)busy->addr);
 
 		vmap_start = (unsigned long) busy->addr + busy->size;
 	}
 
-	if (vmap_end - vmap_start > 0) {
-		free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
-		if (!WARN_ON_ONCE(!free)) {
-			free->va_start = vmap_start;
-			free->va_end = vmap_end;
-
-			insert_vmap_area_augment(free, NULL,
-				&free_vmap_area_root,
-					&free_vmap_area_list);
-		}
-	}
+	if (vmap_end - vmap_start > 0)
+		vmap_insert_free_area(vmap_start, vmap_end);
 }
 
 static void vmap_init_nodes(void)

-- 
2.25.1